Kyushu University Academic Staff Educational and Research Activities Database
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Ryu Matsuo Last modified date:2022.05.13

Associate Professor / Department of Health Care Administration and Management
Department of Basic Medicine
Faculty of Medical Sciences

Graduate School
Other Organization

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 Reseacher Profiling Tool Kyushu University Pure
Academic Degree
M.D., Ph.D.
Country of degree conferring institution (Overseas)
Field of Specialization
internal medicine, stroke, geriatrics, epidemiology
Total Priod of education and research career in the foreign country
Research Interests
  • Epidemiology in Stroke
    keyword : stroke, epidemiology, cohort
  • Research for biomarkers in stroke
    keyword : biomarker, stroke
  • Genetic factor in Stroke
    keyword : genetics, stroke, SNP
  • Association between stroke and air pollution
    keyword : stroke, air pollution
  • Stroke and health economics
    keyword : Stroke, health economics
  • Disability-adjusted Long-term Prognosis in Ischemic Stroke Patients Using Stroke Registry
    keyword : Stroke, QOL, DALY, cohort
Academic Activities
1. Matsuo, Ryu, Ago, Tetsuro, Kiyuna, Fumi, Sato, Noriko, Nakamura, Kuniyuki, Kuroda, Junya, Wakisaka, Yoshinobu, Kitazono, Takanari, Smoking Status and Functional Outcomes After Acute Ischemic Stroke, Stroke, 10.1161/STROKEAHA.119.027230, 51, 3, 846-852, 2020.03, Background and Purpose—Smoking is an established risk factor for stroke; however, it is uncertain whether prestroke smoking status affects clinical outcomes of acute ischemic stroke. This study aimed to elucidate the association between smoking status and functional outcomes after acute ischemic stroke. Methods—Using a multicenter hospital-based stroke registry in Japan, we investigated 10 825 patients with acute ischemic stroke hospitalized between July 2007 and December 2017 who had been independent before stroke onset. Smoking status was categorized into those who had never smoked (nonsmokers), former smokers, and current smokers. Clinical outcomes included poor functional outcome (modified Rankin Scale score ≥2) and functional dependence (modified Rankin Scale score 2–5) at 3 months. We adjusted for potential confounding factors using a logistic regression analysis. Results—The mean age of patients was 70.2±12.2 years, and 37.0% were women. There were 4396 (42.7%) nonsmokers, 3328 (32.4%) former smokers, and 2561 (24.9%) current smokers. The odds ratio (95% CI) for poor functional outcome after adjusting for confounders increased in current smokers (1.29 [1.11–1.49] versus nonsmokers) but not in former smokers (1.05 [0.92–1.21] versus nonsmokers). However, among the former smokers, the odds ratio of poor functional outcome was higher in those who quit smoking within 2 years of stroke onset (1.75 [1.15–2.66] versus nonsmokers). The risk of poor functional outcome tended to increase as the number of daily cigarettes increased in current smokers (P for trend=0.002). All these associations were maintained for functional dependence. Conclusions—Current and recent smoking is associated with an increased risk of unfavorable functional outcomes at 3 months after acute ischemic stroke..
2. ryu matsuo, Yuko Yamaguchi, Tomonaga Matsushita, Jun Hata, Fumi Kiyuna, Kenji Fukuda, Yoshinobu Wakisaka, Junya Kuroda, Tetsuro Ago, Takanari Kitazono, Masahiro Kamouchi, Takao Ishitsuka, Setsuro Ibayashi, Kenji Kusuda, Kenichiro Fujii, Tetsuhiko Nagao, Yasushi Okada, Masahiro Yasaka, Hiroaki Ooboshi, Katsumi Irie, Tsuyoshi Omae, Kazunori Toyoda, Hiroshi Nakane, Hiroshi Sugimori, Shuji Arakawa, Jiro Kitayama, Shigeru Fujimoto, Shoji Arihiro, Yoshihisa Fukushima, Association between onset-to-door time and clinical outcomes after ischemic stroke, Stroke, 10.1161/STROKEAHA.117.018132, 48, 11, 3049-3056, 2017.11, Background and Purpose-The role of early hospital arrival in improving poststroke clinical outcomes in patients without reperfusion treatment remains unclear. This study aimed to determine whether early hospital arrival was associated with favorable outcomes in patients without reperfusion treatment or with minor stroke. Methods-This multicenter, hospital-based study included 6780 consecutive patients (aged, 69.9±12.2 years; 63.9% men) with ischemic stroke who were prospectively registered in Fukuoka, Japan, between July 2007 and December 2014. Onset-to-door time was categorized as T
, ≤1 hour; T
, >1 and ≤2 hours; T
, >2 and ≤3 hours; T
, >3 and ≤6 hours; T
, >6 and ≤12 hours; T
, >12 and ≤24 hours; and T
-, >24 hours. The main outcomes were neurological improvement (decrease in National Institutes of Health Stroke Scale score of ≥4 during hospitalization or 0 at discharge) and good functional outcome (3-month modified Rankin Scale score of 0-1). Associations between onset-to-door time and main outcomes were evaluated after adjusting for potential confounders using logistic regression analysis. Results-Odds ratios (95% confidence intervals) increased significantly with shorter onset-to-door times within 6 hours, for both neurological improvement (T
, 2.79 [2.28-3.42]; T
, 2.49 [2.0
.07]; T
, 1.52 [1.21-1.92]; T
, 1.72 [1.44-2.05], with reference to T
-) and good functional outcome (T
, 2.68 [2.05-3.49], T
2.10 [1.60-2.77], T
1.53 [1.15-2.03], T
1.31 [1.05-1.64], with reference to T
), even after adjusting for potential confounding factors including reperfusion treatment and basal National Institutes of Health Stroke Scale. These associations were maintained in 6216 patients without reperfusion treatment and in 4793 patients with minor stroke (National Institutes of Health Stroke Scale ≤4 on hospital arrival). Conclusions-Early hospital arrival within 6 hours after stroke onset is associated with favorable outcomes after ischemic stroke, regardless of reperfusion treatment or stroke severity..
3. ryu matsuo, Masahiro Kamouchi, Timing of anticoagulant therapy after acute ischemic stroke, Circulation Journal, 10.1253/circj.CJ-16-1287, 81, 2, 151-152, 2017.01.
4. ryu matsuo, Takehiro Michikawa, Kayo Ueda, Tetsuro Ago, Hiroshi Nitta, Takanari Kitazono, Masahiro Kamouchi, Short-Term Exposure to Fine Particulate Matter and Risk of Ischemic Stroke, Stroke, 10.1161/STROKEAHA.116.015303, 47, 12, 3032-3034, 2016.12, Background and Purpose - There is a strong association between ambient concentrations of particulate matter (PM) and cardiovascular disease. However, it remains unclear whether acute exposure to fine PM (PM 2.5) triggers ischemic stroke events and whether the timing of exposure is associated with stroke risk. We, therefore, examined the association between ambient PM 2.5 and occurrence of ischemic stroke. Methods - We analyzed data for 6885 ischemic stroke patients from a multicenter hospital-based stroke registry in Japan who were previously independent and hospitalized within 24 hours of stroke onset. Time of symptom onset was confirmed, and the association between PM (suspended PM and PM 2.5) and occurrence of ischemic stroke was analyzed by time-stratified case-crossover analysis. Results - Ambient PM 2.5 and suspended PM at lag days 0 to 1 were associated with subsequent occurrence of ischemic stroke (ambient temperature-adjusted odds ratio [95% confidence interval] per 10 μg/m 3: suspended PM, 1.02 [1.00-1.05]; PM 2.5, 1.03 [1.00-1.06]). In contrast, ambient suspended PM and PM 2.5 at lag days 2 to 3 or 4 to 6 showed no significant association with stroke occurrence. The association between PM 2.5 at lag days 0 to 1 and ischemic stroke was maintained after adjusting for other air pollutants (nitrogen dioxide, photochemical oxidants, or sulfur dioxide) or influenza epidemics and was evident in the cold season. Conclusions - These findings suggest that short-term exposure to PM 2.5 within 1 day before onset is associated with the subsequent occurrence of ischemic stroke..
5. Ryu matsuo, Tetsuro Ago, Jun Hata, Yoshinobu Wakisaka, Junya Kuroda, Takahiro Kuwashiro, Takanari Kitazono, Masahiro Kamouchi, Plasma C-reactive protein and clinical outcomes after acute ischemic stroke A prospective observational study, PloS one, 10.1371/journal.pone.0156790, 11, 6, 2016.06, Background and Purpose: Although plasma C-reactive protein (CRP) is elevated in response to inflammation caused by brain infarction, the association of CRP with clinical outcomes after acute ischemic stroke remains uncertain. This study examined whether plasma high-sensitivity CRP (hsCRP) levels at onset were associated with clinical outcomes after acute ischemic stroke independent of conventional risk factors and acute infections after stroke. Methods: We prospectively included 3653 patients with first-ever ischemic stroke who had been functionally independent and were hospitalized within 24 h of onset. Plasma hsCRP levels were measured on admission and categorized into quartiles. The association between hsCRP levels and clinical outcomes, including neurological improvement, neurological deterioration, and poor functional outcome (modified Rankin scale ≥3 at 3 months), were investigated using a logistic regression analysis. Results: Higher hsCRP levels were significantly associated with unfavorable outcomes after adjusting for age, sex, baseline National Institutes of Health Stroke Scale score, stroke subtype, conventional risk factors, intravenous thrombolysis and endovascular therapy, and acute infections during hospitalization (multivariate-adjusted odds ratios [95% confidence interval] in the highest quartile versus the lowest quartile as a reference: 0.80 [0.65-0.97] for neurological improvement, 1.72 [1.26-2.34] for neurological deterioration, and 2.03 [1.55-2.67] for a poor functional outcome). These associations were unchanged after excluding patients with infectious diseases occurring during hospitalization, or those with stroke recurrence or death. These trends were similar irrespective of stroke subtypes or baseline stroke severity, but more marked in patients aged <70 years (Pheterogeneity = 0.001). Conclusions: High plasma hsCRP is independently associated with unfavorable clinical outcomes after acute ischemic stroke..
6. Matsuo, Ryu; Kamouchi, Masahiro; Fukuda, Haruhisa; Hata, Jun; Wakisaka, Yoshinobu; Kuroda, Junya; Ago, Tetsuro; Kitazono, Takanari, Intravenous Thrombolysis with Recombinant Tissue Plasminogen Activator for Ischemic Stroke Patients over 80 Years Old: The Fukuoka Stroke Registry, PLOS ONE, 10.1371/journal.pone.0110444, 9, 10, 2014.10.
7. Matsuo, Ryu; Kamouchi, Masahiro; Ago, Tetsuro; Hata, Jun; Shono, Yuji; Kuroda, Junya; Wakisaka, Yoshinobu; Sugimori, Hiroshi; Kitazono, Takanari, Thrombolytic therapy with intravenous recombinant tissue plasminogen activator in Japanese older patients with acute ischemic stroke: Fukuoka Stroke Registry, GERIATRICS & GERONTOLOGY INTERNATIONAL, 10.1111/ggi.12205, 14, 4, 954-959, 2014.10.
8. Matsuo, Ryu; Ago, Tetsuro; Hata, Jun; Kuroda, Junya; Wakisaka, Yoshinobu; Sugimori, Hiroshi; Kitazono, Takanari; Kamouchi, Masahiro, Impact of the 1425G/A Polymorphism of PRKCH on the Recurrence of Ischemic Stroke: Fukuoka Stroke Registry, JOURNAL OF STROKE & CEREBROVASCULAR DISEASES, 10.1016/j.jstrokecerebrovasdis.2013.11.011, 23, 6, 1356-1361, 2014.07.
9. Matsuo, Ryu; Ago, Tetsuro; Kamouchi, Masahiro; Kuroda, Junya; Kuwashiro, Takahiro; Hata, Jun; Sugimori, Hiroshi; Fukuda, Kenji; Gotoh, Seiji; Makihara, Noriko; Fukuhara, Masayo; Awano, Hideto; Isomura, Tetsu; Suzuki, Kazuo; Yasaka, Masahiro; Okada, Yasushi; Kiyohara, Yutaka; Kitazono, Takanari, Clinical significance of plasma VEGF value in ischemic stroke - research for biomarkers in ischemic stroke (REBIOS) study, BMC NEUROLOGY, 10.1186/1471-2377-13-32, 13, 2013.04.
1. Matsuo R, Ago T, Kiyuna, F, Sato, N, Nakamura, K, Wakisaka Y, Kamouchi M, Kitazono T., Smoking status and functional outcomes after acute ischemic stroke, 5th European Stroke Organisation Conference 2019 (ESOC2019), 2019.05.
2. Matuso R; Michikawa T; Ago T; Ueda K; Yamazaki S; Nitta H; Takami A; Kamouchi M; Kitazono T, Short-term exposure to fine particulate matter (PM2.5) and risk of ischemic stroke in Japan, 11th World Stroke Congress 2018, 2018.10.
3. Ago T, Matsuo R, Hata J, Wakisaka Y, Kuroda J, Kitazono T, Kamouchi M, Insulin resistance and clinical outcomes after acute ischemic stroke, 4th European Stroke Organisation Conference, 2018.05.
4. Michikawa T, Matsuo R, Ueda K, Ago T, Nitta H, Kitazono T, Kamouchi M, Short-term exposure to fine particulate matter increased hospital admissions for ischaemic stroke in Japan., Annual Scientific Conference of the International Society of Environmental Epidemiology 2017, 2017.09.
5. Matsuo R, Yamaguchi Y, Matsushita T, Fukuda K, Kiyuna F, Wakisaka Y, Kuroda J, Ago T, Kamouchi M, Kitazono T, Impact of onset-to-door time on clinical outcomes in patients with acute ischemic stroke: the Fukuoka Stroke Registry. , The 3rd European Stroke Organisation Conference 2017, 2017.05.
6. Matsuo R, Yamaguchi Y, Kamouchi M, Sugimori H, Shono Y, Ago T, Kitazono T. , Association between neurological symptoms at stroke onset and use of ambulance– the Fukuoka Stroke Registry., Asia Pacific Stroke Conference 2016, 2016.07.
7. Noichi Y, Matsuo R, Kamouchi M, Furukawa S, Kitamura T, Ito Y, Murao K, Arakawa S, Ago T, Kitazono T, Informed consent in a multicenter stroke registry: Fukuoka Stroke Registry. , Asia Pacific Stroke Conference 2016, 2016.07.
8. Kiyuna F, Matsuo R, Wakisaka Y, Kuroda J, Ago T, Kamouchi M, Kitazono T, Association between high-sensitivity CRP at stroke onset and clinical outcomes in patients with small vessel occlusion. , 2nd. European Stroke Organisation Conference 2016, 2016.05.
9. Matsuo R, Kamouchi M, Hata J, Wakisaka Y, Kuroda J, Ago T, Kitazono T, Pioglitazone treatment and long-term post-stroke prognosis in diabetic patients with acute ischemic stroke: the Fukuoka Stroke Registry. , Asia Pacific Stroke Conference 2015, 2015.10.
10. Matsuo R, Kamouchi M, Hata J, Wakisaka Y, Kuroda J, Ago T, Kitazono T, Association of high-sensitivity C-reactive protein at stroke onset with short-term clinical outcomes after ischemic stroke: the Fukuoka Stroke Registry, 1st . European Stroke Organisation Conference 2015, 2015.04.